support event prop on <router-link> (close #785, #786)

Author: yyx990803

examples/basic/app.js

@@ -34,7 +34,9 @@ new Vue({
         <li><router-link to="/">/</router-link></li>
         <li><router-link to="/foo">/foo</router-link></li>
         <li><router-link to="/bar">/bar</router-link></li>
-        <router-link tag="li" to="/bar">/bar</router-link>
+        <router-link tag="li" to="/bar" :event="['mousedown', 'touchstart']">
+          <a>/bar</a>
+        </router-link>
       </ul>
       <router-view class="view"></router-view>
     </div>

src/components/link.js

@@ -20,7 +20,11 @@ export default {
     exact: Boolean,
     append: Boolean,
     replace: Boolean,
-    activeClass: String
+    activeClass: String,
+    event: {
+      type: [String, Array],
+      default: 'click'
+    }
   },
   render (h: Function) {
     const router = this.$router
@@ -33,23 +37,8 @@ export default {
       ? isSameRoute(current, compareTarget)
       : isIncludedRoute(current, compareTarget)
 
-    const on = {
-      click: (e) => {
-        // don't redirect with control keys
-        /* istanbul ignore if */
-        if (e.metaKey || e.ctrlKey || e.shiftKey) return
-        // don't redirect when preventDefault called
-        /* istanbul ignore if */
-        if (e.defaultPrevented) return
-        // don't redirect on right click
-        /* istanbul ignore if */
-        if (e.button !== 0) return
-        // don't redirect if `target="_blank"`
-        /* istanbul ignore if */
-        const target = e.target.getAttribute('target')
-        if (/\b_blank\b/i.test(target)) return
-
-        e.preventDefault()
+    const handler = e => {
+      if (guardEvent(e)) {
         if (this.replace) {
           router.replace(normalizedTo)
         } else {
@@ -58,6 +47,13 @@ export default {
       }
     }
 
+    const on = { click: guardEvent }
+    if (Array.isArray(this.event)) {
+      this.event.forEach(e => { on[e] = handler })
+    } else {
+      on[this.event] = handler
+    }
+
     const data: any = {
       class: classes
     }
@@ -86,6 +82,25 @@ export default {
   }
 }
 
+function guardEvent (e) {
+  // don't redirect with control keys
+  /* istanbul ignore if */
+  if (e.metaKey || e.ctrlKey || e.shiftKey) return
+  // don't redirect when preventDefault called
+  /* istanbul ignore if */
+  if (e.defaultPrevented) return
+  // don't redirect on right click
+  /* istanbul ignore if */
+  if (e.button !== 0) return
+  // don't redirect if `target="_blank"`
+  /* istanbul ignore if */
+  const target = e.target.getAttribute('target')
+  if (/\b_blank\b/i.test(target)) return
+
+  e.preventDefault()
+  return true
+}
+
 function findAnchor (children) {
   if (children) {
     let child

test/e2e/specs/basic.js

@@ -4,11 +4,12 @@ module.exports = {
     .url('http://localhost:8080/basic/')
       .waitForElementVisible('#app', 1000)
       .assert.count('li', 4)
-      .assert.count('li a', 3)
+      .assert.count('li a', 4)
       // assert correct href with base
       .assert.attributeContains('li:nth-child(1) a', 'href', '/basic/')
       .assert.attributeContains('li:nth-child(2) a', 'href', '/basic/foo')
       .assert.attributeContains('li:nth-child(3) a', 'href', '/basic/bar')
+      .assert.attributeContains('li:nth-child(4) a', 'href', '/basic/bar')
       .assert.containsText('.view', 'home')
 
       .click('li:nth-child(2) a')
@@ -23,7 +24,7 @@ module.exports = {
       .assert.urlEquals('http://localhost:8080/basic/')
       .assert.containsText('.view', 'home')
 
-      .click('li:nth-child(4)')
+      .click('li:nth-child(4) a')
       .assert.urlEquals('http://localhost:8080/basic/bar')
       .assert.containsText('.view', 'bar')